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2018-10-23Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes are: - Migrate CPU-intense 'misfit' tasks on asymmetric capacity systems, to better utilize (much) faster 'big core' CPUs. (Morten Rasmussen, Valentin Schneider) - Topology handling improvements, in particular when CPU capacity changes and related load-balancing fixes/improvements (Morten Rasmussen) - ... plus misc other improvements, fixes and updates" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits) sched/completions/Documentation: Add recommendation for dynamic and ONSTACK completions sched/completions/Documentation: Clean up the document some more sched/completions/Documentation: Fix a couple of punctuation nits cpu/SMT: State SMT is disabled even with nosmt and without "=force" sched/core: Fix comment regarding nr_iowait_cpu() and get_iowait_load() sched/fair: Remove setting task's se->runnable_weight during PELT update sched/fair: Disable LB_BIAS by default sched/pelt: Fix warning and clean up IRQ PELT config sched/topology: Make local variables static sched/debug: Use symbolic names for task state constants sched/numa: Remove unused numa_stats::nr_running field sched/numa: Remove unused code from update_numa_stats() sched/debug: Explicitly cast sched_feat() to bool sched/core: Disable SD_PREFER_SIBLING on asymmetric CPU capacity domains sched/fair: Don't move tasks to lower capacity CPUs unless necessary sched/fair: Set rq->rd->overload when misfit sched/fair: Wrap rq->rd->overload accesses with READ/WRITE_ONCE() sched/core: Change root_domain->overload type to int sched/fair: Change 'prefer_sibling' type to bool sched/fair: Kick nohz balance if rq->misfit_task_load ...
2018-10-23Merge branch 'locking-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking and misc x86 updates from Ingo Molnar: "Lots of changes in this cycle - in part because locking/core attracted a number of related x86 low level work which was easier to handle in a single tree: - Linux Kernel Memory Consistency Model updates (Alan Stern, Paul E. McKenney, Andrea Parri) - lockdep scalability improvements and micro-optimizations (Waiman Long) - rwsem improvements (Waiman Long) - spinlock micro-optimization (Matthew Wilcox) - qspinlocks: Provide a liveness guarantee (more fairness) on x86. (Peter Zijlstra) - Add support for relative references in jump tables on arm64, x86 and s390 to optimize jump labels (Ard Biesheuvel, Heiko Carstens) - Be a lot less permissive on weird (kernel address) uaccess faults on x86: BUG() when uaccess helpers fault on kernel addresses (Jann Horn) - macrofy x86 asm statements to un-confuse the GCC inliner. (Nadav Amit) - ... and a handful of other smaller changes as well" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits) locking/lockdep: Make global debug_locks* variables read-mostly locking/lockdep: Fix debug_locks off performance problem locking/pvqspinlock: Extend node size when pvqspinlock is configured locking/qspinlock_stat: Count instances of nested lock slowpaths locking/qspinlock, x86: Provide liveness guarantee x86/asm: 'Simplify' GEN_*_RMWcc() macros locking/qspinlock: Rework some comments locking/qspinlock: Re-order code locking/lockdep: Remove duplicated 'lock_class_ops' percpu array x86/defconfig: Enable CONFIG_USB_XHCI_HCD=y futex: Replace spin_is_locked() with lockdep locking/lockdep: Make class->ops a percpu counter and move it under CONFIG_DEBUG_LOCKDEP=y x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs x86/cpufeature: Macrofy inline assembly code to work around GCC inlining bugs x86/extable: Macrofy inline assembly code to work around GCC inlining bugs x86/paravirt: Work around GCC inlining bugs when compiling paravirt ops x86/bug: Macrofy the BUG table section handling, to work around GCC inlining bugs x86/alternatives: Macrofy lock prefixes to work around GCC inlining bugs x86/refcount: Work around GCC inlining bug x86/objtool: Use asm macros to work around GCC inlining bugs ...
2018-10-09init: add arch_call_rest_init to allow stack switchingMartin Schwidefsky
With CONFIG_VMAP_STACK=y the kernel stack of all tasks should be allocated in the vmalloc space. The initial stack used for all the early init code is in the init_thread_union. To be able to switch from this early stack to a properly allocated stack from vmalloc the architecture needs a switch-over point. Introduce the arch_call_rest_init() function with a weak definition in init/main.c with the only purpose to call rest_init() from the end of start_kernel(). The architecture override can then do the necessary magic to switch to the new vmalloc'ed stack. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-02sched/pelt: Fix warning and clean up IRQ PELT configVincent Guittot
Create a config for enabling irq load tracking in the scheduler. irq load tracking is useful only when irq or paravirtual time is accounted but it's only possible with SMP for now. Also use __maybe_unused to remove the compilation warning in update_rq_clock_task() that has been introduced by: 2e62c4743adc ("sched/fair: Remove #ifdefs from scale_rt_capacity()") Suggested-by: Ingo Molnar <mingo@redhat.com> Reported-by: Dou Liyang <douly.fnst@cn.fujitsu.com> Reported-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bp@alien8.de Cc: dou_liyang@163.com Fixes: 2e62c4743adc ("sched/fair: Remove #ifdefs from scale_rt_capacity()") Link: http://lkml.kernel.org/r/1537867062-27285-1-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-27jump_label: Annotate entries that operate on __init code earlierArd Biesheuvel
Jump table entries are mostly read-only, with the exception of the init and module loader code that defuses entries that point into init code when the code being referred to is freed. For robustness, it would be better to move these entries into the ro_after_init section, but clearing the 'code' member of each jump table entry referring to init code at module load time races with the module_enable_ro() call that remaps the ro_after_init section read only, so we'd like to do it earlier. So given that whether such an entry refers to init code can be decided much earlier, we can pull this check forward. Since we may still need the code entry at this point, let's switch to setting a low bit in the 'key' member just like we do to annotate the default state of a jump table entry. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-s390@vger.kernel.org Cc: Arnd Bergmann <arnd@arndb.de> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Jessica Yu <jeyu@kernel.org> Link: https://lkml.kernel.org/r/20180919065144.25010-8-ard.biesheuvel@linaro.org
2018-08-25Merge tag 'kbuild-v4.19-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull more Kbuild updates from Masahiro Yamada: - add build_{menu,n,g,x}config targets for compile-testing Kconfig - fix and improve recursive dependency detection in Kconfig - fix parallel building of menuconfig/nconfig - fix syntax error in clang-version.sh - suppress distracting log from syncconfig - remove obsolete "rpm" target - remove VMLINUX_SYMBOL(_STR) macro entirely - fix microblaze build with CONFIG_DYNAMIC_FTRACE - move compiler test for dead code/data elimination to Kconfig - rename well-known LDFLAGS variable to KBUILD_LDFLAGS - misc fixes and cleanups * tag 'kbuild-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kbuild: rename LDFLAGS to KBUILD_LDFLAGS kbuild: pass LDFLAGS to recordmcount.pl kbuild: test dead code/data elimination support in Kconfig initramfs: move gen_initramfs_list.sh from scripts/ to usr/ vmlinux.lds.h: remove stale <linux/export.h> include export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() Coccinelle: remove pci_alloc_consistent semantic to detect in zalloc-simple.cocci kbuild: make sorting initramfs contents independent of locale kbuild: remove "rpm" target, which is alias of "rpm-pkg" kbuild: Fix LOADLIBES rename in Documentation/kbuild/makefiles.txt kconfig: suppress "configuration written to .config" for syncconfig kconfig: fix "Can't open ..." in parallel build kbuild: Add a space after `!` to prevent parsing as file pattern scripts: modpost: check memory allocation results kconfig: improve the recursive dependency report kconfig: report recursive dependency involving 'imply' kconfig: error out when seeing recursive dependency kconfig: add build-only configurator targets scripts/dtc: consolidate include path options in Makefile
2018-08-24kbuild: test dead code/data elimination support in KconfigMasahiro Yamada
This config option should be enabled only when both the compiler and the linker support necessary flags. Add proper dependencies to Kconfig. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-08-22Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge more updates from Andrew Morton: - the rest of MM - procfs updates - various misc things - more y2038 fixes - get_maintainer updates - lib/ updates - checkpatch updates - various epoll updates - autofs updates - hfsplus - some reiserfs work - fatfs updates - signal.c cleanups - ipc/ updates * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (166 commits) ipc/util.c: update return value of ipc_getref from int to bool ipc/util.c: further variable name cleanups ipc: simplify ipc initialization ipc: get rid of ids->tables_initialized hack lib/rhashtable: guarantee initial hashtable allocation lib/rhashtable: simplify bucket_table_alloc() ipc: drop ipc_lock() ipc/util.c: correct comment in ipc_obtain_object_check ipc: rename ipcctl_pre_down_nolock() ipc/util.c: use ipc_rcu_putref() for failues in ipc_addid() ipc: reorganize initialization of kern_ipc_perm.seq ipc: compute kern_ipc_perm.id under the ipc lock init/Kconfig: remove EXPERT from CHECKPOINT_RESTORE fs/sysv/inode.c: use ktime_get_real_seconds() for superblock stamp adfs: use timespec64 for time conversion kernel/sysctl.c: fix typos in comments drivers/rapidio/devices/rio_mport_cdev.c: remove redundant pointer md fork: don't copy inconsistent signal handler state to child signal: make get_signal() return bool signal: make sigkill_pending() return bool ...
2018-08-22init/Kconfig: remove EXPERT from CHECKPOINT_RESTOREAdrian Reber
The CHECKPOINT_RESTORE configuration option was introduced in 2012 and combined with EXPERT. CHECKPOINT_RESTORE is already enabled in many distribution kernels and also part of the defconfigs of various architectures. To make it easier for distributions to enable CHECKPOINT_RESTORE this removes EXPERT and moves the configuration option out of the EXPERT block. Link: http://lkml.kernel.org/r/20180712130733.11510-1-adrian@lisas.de Signed-off-by: Adrian Reber <adrian@lisas.de> Acked-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com> Acked-by: Pavel Emelyanov <xemul@virtuozzo.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Andrei Vagin <avagin@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22init/main.c: log init process file namePaul Menzel
Add a log message to `run_init_process()`. This log message serves two purposes. 1. If the init process is not specified on the Linux Kernel command line, the user sees, what file was chosen. 2. The time stamps shows exactly, when the Linux kernel handed over control to the init process. Link: http://lkml.kernel.org/r/b1fc97fa-4aa9-1904-ddb5-859e78995c41@molgen.mpg.de Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22init/Kconfig: fix its typosRandy Dunlap
Correct typos of "it's" to "its. Link: http://lkml.kernel.org/r/0ac627b6-5527-55f4-0489-1631aa34fc11@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22init/: remove ineffective sparse disablingLuc Van Oostenryck
Sparse checking used to be disabled on init/do_mounts.c and a few related files because "Many of the syscalls used in this file expect some of the arguments to be __user pointers not __kernel pointers". However since 28128c61e ("kconfig.h: Include compiler types to avoid missed struct attributes") the checks are, in fact, not disabled anymore because of the more early include of "linux/compiler_types.h" So remove the now ineffective #undefery that was done to disable these warnings, as well as the associated comment. Link: http://lkml.kernel.org/r/20180617115355.53799-1-luc.vanoostenryck@gmail.com Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-22init: allow initcall tables to be emitted using relative referencesArd Biesheuvel
Allow the initcall tables to be emitted using relative references that are only half the size on 64-bit architectures and don't require fixups at runtime on relocatable kernels. Link: http://lkml.kernel.org/r/20180704083651.24360-5-ard.biesheuvel@linaro.org Acked-by: James Morris <james.morris@microsoft.com> Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Petr Mladek <pmladek@suse.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morris <jmorris@namei.org> Cc: Jessica Yu <jeyu@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Nicolas Pitre <nico@linaro.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Russell King <linux@armlinux.org.uk> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Garnier <thgarnie@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-21Merge branch 'siginfo-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull core signal handling updates from Eric Biederman: "It was observed that a periodic timer in combination with a sufficiently expensive fork could prevent fork from every completing. This contains the changes to remove the need for that restart. This set of changes is split into several parts: - The first part makes PIDTYPE_TGID a proper pid type instead something only for very special cases. The part starts using PIDTYPE_TGID enough so that in __send_signal where signals are actually delivered we know if the signal is being sent to a a group of processes or just a single process. - With that prep work out of the way the logic in fork is modified so that fork logically makes signals received while it is running appear to be received after the fork completes" * 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (22 commits) signal: Don't send signals to tasks that don't exist signal: Don't restart fork when signals come in. fork: Have new threads join on-going signal group stops fork: Skip setting TIF_SIGPENDING in ptrace_init_task signal: Add calculate_sigpending() fork: Unconditionally exit if a fatal signal is pending fork: Move and describe why the code examines PIDNS_ADDING signal: Push pid type down into complete_signal. signal: Push pid type down into __send_signal signal: Push pid type down into send_signal signal: Pass pid type into do_send_sig_info signal: Pass pid type into send_sigio_to_task & send_sigurg_to_task signal: Pass pid type into group_send_sig_info signal: Pass pid and pid type into send_sigqueue posix-timers: Noralize good_sigevent signal: Use PIDTYPE_TGID to clearly store where file signals will be sent pid: Implement PIDTYPE_TGID pids: Move the pgrp and session pid pointers from task_struct to signal_struct kvm: Don't open code task_pid in kvm_vcpu_ioctl pids: Compute task_tgid using signal->leader_pid ...
2018-08-20Merge tag 'trace-v4.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - Restructure of lockdep and latency tracers This is the biggest change. Joel Fernandes restructured the hooks from irqs and preemption disabling and enabling. He got rid of a lot of the preprocessor #ifdef mess that they caused. He turned both lockdep and the latency tracers to use trace events inserted in the preempt/irqs disabling paths. But unfortunately, these started to cause issues in corner cases. Thus, parts of the code was reverted back to where lockdep and the latency tracers just get called directly (without using the trace events). But because the original change cleaned up the code very nicely we kept that, as well as the trace events for preempt and irqs disabling, but they are limited to not being called in NMIs. - Have trace events use SRCU for "rcu idle" calls. This was required for the preempt/irqs off trace events. But it also had to not allow them to be called in NMI context. Waiting till Paul makes an NMI safe SRCU API. - New notrace SRCU API to allow trace events to use SRCU. - Addition of mcount-nop option support - SPDX headers replacing GPL templates. - Various other fixes and clean ups. - Some fixes are marked for stable, but were not fully tested before the merge window opened. * tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits) tracing: Fix SPDX format headers to use C++ style comments tracing: Add SPDX License format tags to tracing files tracing: Add SPDX License format to bpf_trace.c blktrace: Add SPDX License format header s390/ftrace: Add -mfentry and -mnop-mcount support tracing: Add -mcount-nop option support tracing: Avoid calling cc-option -mrecord-mcount for every Makefile tracing: Handle CC_FLAGS_FTRACE more accurately Uprobe: Additional argument arch_uprobe to uprobe_write_opcode() Uprobes: Simplify uprobe_register() body tracepoints: Free early tracepoints after RCU is initialized uprobes: Use synchronize_rcu() not synchronize_sched() tracing: Fix synchronizing to event changes with tracepoint_synchronize_unregister() ftrace: Remove unused pointer ftrace_swapper_pid tracing: More reverting of "tracing: Centralize preemptirq tracepoints and unify their usage" tracing/irqsoff: Handle preempt_count for different configs tracing: Partial revert of "tracing: Centralize preemptirq tracepoints and unify their usage" tracing: irqsoff: Account for additional preempt_disable trace: Use rcu_dereference_raw for hooks from trace-event subsystem tracing/kprobes: Fix within_notrace_func() to check only notrace functions ...
2018-08-17mm: introduce CONFIG_MEMCG_KMEM as combination of CONFIG_MEMCG && !CONFIG_SLOBKirill Tkhai
Introduce new config option, which is used to replace repeating CONFIG_MEMCG && !CONFIG_SLOB pattern. Next patches add a little more memcg+kmem related code, so let's keep the defines more clearly. Link: http://lkml.kernel.org/r/153063053670.1818.15013136946600481138.stgit@localhost.localdomain Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Acked-by: Vladimir Davydov <vdavydov.dev@gmail.com> Tested-by: Shakeel Butt <shakeelb@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Josef Bacik <jbacik@fb.com> Cc: Li RongQing <lirongqing@baidu.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matthias Kaehlcke <mka@chromium.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Roman Gushchin <guro@fb.com> Cc: Sahitya Tummala <stummala@codeaurora.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-15Merge tag 'kconfig-v4.19-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kconfig consolidation from Masahiro Yamada: "Consolidation of Kconfig files by Christoph Hellwig. Move the source statements of arch-independent Kconfig files instead of duplicating the includes in every arch/$(SRCARCH)/Kconfig" * tag 'kconfig-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kconfig: add a Memory Management options" menu kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt kconfig: use a menu in arch/Kconfig to reduce clutter kconfig: include kernel/Kconfig.preempt from init/Kconfig Kconfig: consolidate the "Kernel hacking" menu kconfig: include common Kconfig files from top-level Kconfig kconfig: remove duplicate SWAP symbol defintions um: create a proper drivers Kconfig um: cleanup Kconfig files um: stop abusing KBUILD_KCONFIG
2018-08-15Merge tag 'kconfig-v4.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kconfig updates from Masahiro Yamada: - show clearer error messages where pkg-config is needed, but not installed - rename SYMBOL_AUTO to SYMBOL_NO_WRITE to reflect its semantics - create all necessary directories by Kconfig tool itself instead of Makefile - update the .config unconditionally when syncconfig is invoked - use 'include' directive instead of '-include' where include/config/{auto,tristate}.conf is mandatory - do not try to update the .config when running install targets - add .DELETE_ON_ERROR to delete partially updated files - misc cleanups and fixes * tag 'kconfig-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kconfig: remove P_ENV property type kconfig: remove unused sym_get_env_prop() function kconfig: fix the rule of mainmenu_stmt symbol init/Kconfig: Use short unix-style option instead of --longname Kbuild: Makefile.modbuiltin: include auto.conf and tristate.conf mandatory kbuild: remove auto.conf from prerequisite of phony targets kbuild: do not update config for 'make kernelrelease' kbuild: do not update config when running install targets kbuild: add .DELETE_ON_ERROR special target kbuild: use 'include' directive to load auto.conf from top Makefile kconfig: allow all config targets to write auto.conf if missing kconfig: make syncconfig update .config regardless of sym_change_count kconfig: create directories needed for syncconfig by itself kconfig: remove unneeded directory generation from local*config kconfig: split out useful helpers in confdata.c kconfig: rename file_write_dep and move it to confdata.c kconfig: fix typos in description of "choice" in kconfig-language.txt kconfig: handle format string before calling conf_message_callback() kconfig: rename SYMBOL_AUTO to SYMBOL_NO_WRITE kconfig: check for pkg-config on make {menu,n,g,x}config
2018-08-15Merge tag 'kbuild-v4.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - verify depmod is installed before modules_install - support build salt in case build ids must be unique between builds - allow users to specify additional host compiler flags via HOST*FLAGS, and rename internal variables to KBUILD_HOST*FLAGS - update buildtar script to drop vax support, add arm64 support - update builddeb script for better debarch support - document the pit-fall of if_changed usage - fix parallel build of UML with O= option - make 'samples' target depend on headers_install to fix build errors - remove deprecated host-progs variable - add a new coccinelle script for refcount_t vs atomic_t check - improve double-test coccinelle script - misc cleanups and fixes * tag 'kbuild-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (41 commits) coccicheck: return proper error code on fail Coccinelle: doubletest: reduce side effect false positives kbuild: remove deprecated host-progs variable kbuild: make samples really depend on headers_install um: clean up archheaders recipe kbuild: add %asm-generic to no-dot-config-targets um: fix parallel building with O= option scripts: Add Python 3 support to tracing/draw_functrace.py builddeb: Add automatic support for sh{3,4}{,eb} architectures builddeb: Add automatic support for riscv* architectures builddeb: Add automatic support for m68k architecture builddeb: Add automatic support for or1k architecture builddeb: Add automatic support for sparc64 architecture builddeb: Add automatic support for mips{,64}r6{,el} architectures builddeb: Add automatic support for mips64el architecture builddeb: Add automatic support for ppc64 and powerpcspe architectures builddeb: Introduce functions to simplify kconfig tests in set_debarch builddeb: Drop check for 32-bit s390 builddeb: Change architecture detection fallback to use dpkg-architecture builddeb: Skip architecture detection when KBUILD_DEBARCH is set ...
2018-08-13Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Heiko Carstens: "Since Martin is on vacation you get the s390 pull request from me: - Host large page support for KVM guests. As the patches have large impact on arch/s390/mm/ this series goes out via both the KVM and the s390 tree. - Add an option for no compression to the "Kernel compression mode" menu, this will come in handy with the rework of the early boot code. - A large rework of the early boot code that will make life easier for KASAN and KASLR. With the rework the bootable uncompressed image is not generated anymore, only the bzImage is available. For debuggung purposes the new "no compression" option is used. - Re-enable the gcc plugins as the issue with the latent entropy plugin is solved with the early boot code rework. - More spectre relates changes: + Detect the etoken facility and remove expolines automatically. + Add expolines to a few more indirect branches. - A rewrite of the common I/O layer trace points to make them consumable by 'perf stat'. - Add support for format-3 PCI function measurement blocks. - Changes for the zcrypt driver: + Add attributes to indicate the load of cards and queues. + Restructure some code for the upcoming AP device support in KVM. - Build flags improvements in various Makefiles. - A few fixes for the kdump support. - A couple of patches for gcc 8 compile warning cleanup. - Cleanup s390 specific proc handlers. - Add s390 support to the restartable sequence self tests. - Some PTR_RET vs PTR_ERR_OR_ZERO cleanup. - Lots of bug fixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (107 commits) s390/dasd: fix hanging offline processing due to canceled worker s390/dasd: fix panic for failed online processing s390/mm: fix addressing exception after suspend/resume rseq/selftests: add s390 support s390: fix br_r1_trampoline for machines without exrl s390/lib: use expoline for all bcr instructions s390/numa: move initial setup of node_to_cpumask_map s390/kdump: Fix elfcorehdr size calculation s390/cpum_sf: save TOD clock base in SDBs for time conversion KVM: s390: Add huge page enablement control s390/mm: Add huge page gmap linking support s390/mm: hugetlb pages within a gmap can not be freed KVM: s390: Add skey emulation fault handling s390/mm: Add huge pmd storage key handling s390/mm: Clear skeys for newly mapped huge guest pmds s390/mm: Clear huge page storage keys on enable_skey s390/mm: Add huge page dirty sync support s390/mm: Add gmap pmd invalidation and clearing s390/mm: Add gmap pmd notification bit setting s390/mm: Add gmap pmd linking ...
2018-08-13Merge branch 'x86-timers-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 timer updates from Thomas Gleixner: "Early TSC based time stamping to allow better boot time analysis. This comes with a general cleanup of the TSC calibration code which grew warts and duct taping over the years and removes 250 lines of code. Initiated and mostly implemented by Pavel with help from various folks" * 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits) x86/kvmclock: Mark kvm_get_preset_lpj() as __init x86/tsc: Consolidate init code sched/clock: Disable interrupts when calling generic_sched_clock_init() timekeeping: Prevent false warning when persistent clock is not available sched/clock: Close a hole in sched_clock_init() x86/tsc: Make use of tsc_calibrate_cpu_early() x86/tsc: Split native_calibrate_cpu() into early and late parts sched/clock: Use static key for sched_clock_running sched/clock: Enable sched clock early sched/clock: Move sched clock initialization and merge with generic clock x86/tsc: Use TSC as sched clock early x86/tsc: Initialize cyc2ns when tsc frequency is determined x86/tsc: Calibrate tsc only once ARM/time: Remove read_boot_clock64() s390/time: Remove read_boot_clock64() timekeeping: Default boot time offset to local_clock() timekeeping: Replace read_boot_clock64() with read_persistent_wall_and_boot_offset() s390/time: Add read_persistent_wall_and_boot_offset() x86/xen/time: Output xen sched_clock time from 0 x86/xen/time: Initialize pv xen time in init_hypervisor_platform() ...
2018-08-13Merge branch 'x86/pti' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds
Pull x86 PTI updates from Thomas Gleixner: "The Speck brigade sadly provides yet another large set of patches destroying the perfomance which we carefully built and preserved - PTI support for 32bit PAE. The missing counter part to the 64bit PTI code implemented by Joerg. - A set of fixes for the Global Bit mechanics for non PCID CPUs which were setting the Global Bit too widely and therefore possibly exposing interesting memory needlessly. - Protection against userspace-userspace SpectreRSB - Support for the upcoming Enhanced IBRS mode, which is preferred over IBRS. Unfortunately we dont know the performance impact of this, but it's expected to be less horrible than the IBRS hammering. - Cleanups and simplifications" * 'x86/pti' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits) x86/mm/pti: Move user W+X check into pti_finalize() x86/relocs: Add __end_rodata_aligned to S_REL x86/mm/pti: Clone kernel-image on PTE level for 32 bit x86/mm/pti: Don't clear permissions in pti_clone_pmd() x86/mm/pti: Fix 32 bit PCID check x86/mm/init: Remove freed kernel image areas from alias mapping x86/mm/init: Add helper for freeing kernel image pages x86/mm/init: Pass unconverted symbol addresses to free_init_pages() mm: Allow non-direct-map arguments to free_reserved_area() x86/mm/pti: Clear Global bit more aggressively x86/speculation: Support Enhanced IBRS on future CPUs x86/speculation: Protect against userspace-userspace spectreRSB x86/kexec: Allocate 8k PGDs for PTI Revert "perf/core: Make sure the ring-buffer is mapped in all page-tables" x86/mm: Remove in_nmi() warning from vmalloc_fault() x86/entry/32: Check for VM86 mode in slow-path check perf/core: Make sure the ring-buffer is mapped in all page-tables x86/pti: Check the return value of pti_user_pagetable_walk_pmd() x86/pti: Check the return value of pti_user_pagetable_walk_p4d() x86/entry/32: Add debug code to check entry/exit CR3 ...
2018-08-12init: rename and re-order boot_cpu_state_init()Linus Torvalds
This is purely a preparatory patch for upcoming changes during the 4.19 merge window. We have a function called "boot_cpu_state_init()" that isn't really about the bootup cpu state: that is done much earlier by the similarly named "boot_cpu_init()" (note lack of "state" in name). This function initializes some hotplug CPU state, and needs to run after the percpu data has been properly initialized. It even has a comment to that effect. Except it _doesn't_ actually run after the percpu data has been properly initialized. On x86 it happens to do that, but on at least arm and arm64, the percpu base pointers are initialized by the arch-specific 'smp_prepare_boot_cpu()' hook, which ran _after_ boot_cpu_state_init(). This had some unexpected results, and in particular we have a patch pending for the merge window that did the obvious cleanup of using 'this_cpu_write()' in the cpu hotplug init code: - per_cpu_ptr(&cpuhp_state, smp_processor_id())->state = CPUHP_ONLINE; + this_cpu_write(cpuhp_state.state, CPUHP_ONLINE); which is obviously the right thing to do. Except because of the ordering issue, it actually failed miserably and unexpectedly on arm64. So this just fixes the ordering, and changes the name of the function to be 'boot_cpu_hotplug_init()' to make it obvious that it's about cpu hotplug state, because the core CPU state was supposed to have already been done earlier. Marked for stable, since the (not yet merged) patch that will show this problem is marked for stable. Reported-by: Vlastimil Babka <vbabka@suse.cz> Reported-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com> Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-10tracing: Partial revert of "tracing: Centralize preemptirq tracepoints and ↵Steven Rostedt (VMware)
unify their usage" Joel Fernandes created a nice patch that cleaned up the duplicate hooks used by lockdep and irqsoff latency tracer. It made both use tracepoints. But it caused lockdep to trigger several false positives. We have not figured out why yet, but removing lockdep from using the trace event hooks and just call its helper functions directly (like it use to), makes the problem go away. This is a partial revert of the clean up patch c3bc8fd637a9 ("tracing: Centralize preemptirq tracepoints and unify their usage") that adds direct calls for lockdep, but also keeps most of the clean up done to get rid of the horrible preprocessor if statements. Link: http://lkml.kernel.org/r/20180806155058.5ee875f4@gandalf.local.home Cc: Peter Zijlstra <peterz@infradead.org> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Fixes: c3bc8fd637a9 ("tracing: Centralize preemptirq tracepoints and unify their usage") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-09signal: Don't restart fork when signals come in.Eric W. Biederman
Wen Yang <wen.yang99@zte.com.cn> and majiang <ma.jiang@zte.com.cn> report that a periodic signal received during fork can cause fork to continually restart preventing an application from making progress. The code was being overly pessimistic. Fork needs to guarantee that a signal sent to multiple processes is logically delivered before the fork and just to the forking process or logically delivered after the fork to both the forking process and it's newly spawned child. For signals like periodic timers that are always delivered to a single process fork can safely complete and let them appear to logically delivered after the fork(). While examining this issue I also discovered that fork today will miss signals delivered to multiple processes during the fork and handled by another thread. Similarly the current code will also miss blocked signals that are delivered to multiple process, as those signals will not appear pending during fork. Add a list of each thread that is currently forking, and keep on that list a signal set that records all of the signals sent to multiple processes. When fork completes initialize the new processes shared_pending signal set with it. The calculate_sigpending function will see those signals and set TIF_SIGPENDING causing the new task to take the slow path to userspace to handle those signals. Making it appear as if those signals were received immediately after the fork. It is not possible to send real time signals to multiple processes and exceptions don't go to multiple processes, which means that that are no signals sent to multiple processes that require siginfo. This means it is safe to not bother collecting siginfo on signals sent during fork. The sigaction of a child of fork is initially the same as the sigaction of the parent process. So a signal the parent ignores the child will also initially ignore. Therefore it is safe to ignore signals sent to multiple processes and ignored by the forking process. Signals sent to only a single process or only a single thread and delivered during fork are treated as if they are received after the fork, and generally not dealt with. They won't cause any problems. V2: Added removal from the multiprocess list on failure. V3: Use -ERESTARTNOINTR directly V4: - Don't queue both SIGCONT and SIGSTOP - Initialize signal_struct.multiprocess in init_task - Move setting of shared_pending to before the new task is visible to signals. This prevents signals from comming in before shared_pending.signal is set to delayed.signal and being lost. V5: - rework list add and delete to account for idle threads v6: - Use sigdelsetmask when removing stop signals Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200447 Reported-by: Wen Yang <wen.yang99@zte.com.cn> and Reported-by: majiang <ma.jiang@zte.com.cn> Fixes: 4a2c7a7837da ("[PATCH] make fork() atomic wrt pgrp/session signals") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-08-09init/Kconfig: Use short unix-style option instead of --longnameRob Landley
Avoids warning messages with the latest release of toybox, which never bothered to implement the --longopts nothing was using. Signed-off-by: Rob Landley <rob@landley.net> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-08-02kconfig: include kernel/Kconfig.preempt from init/KconfigChristoph Hellwig
Almost all architectures include it. Add a ARCH_NO_PREEMPT symbol to disable preempt support for alpha, hexagon, non-coldfire m68k and user mode Linux. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-08-02kconfig: include common Kconfig files from top-level KconfigChristoph Hellwig
Instead of duplicating the source statements in every architecture just do it once in the toplevel Kconfig file. Note that with this the inclusion of arch/$(SRCARCH/Kconfig moves out of the top-level Kconfig into arch/Kconfig so that don't violate ordering constraits while keeping a sensible menu structure. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-08-02kconfig: remove duplicate SWAP symbol defintionsChristoph Hellwig
microblaze and nios2 define their own always n SWAP symbols. Remove those and let the generic defintion do the right thing by adding a new symbol to disable swap entirely. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-31tracing: Centralize preemptirq tracepoints and unify their usageJoel Fernandes (Google)
This patch detaches the preemptirq tracepoints from the tracers and keeps it separate. Advantages: * Lockdep and irqsoff event can now run in parallel since they no longer have their own calls. * This unifies the usecase of adding hooks to an irqsoff and irqson event, and a preemptoff and preempton event. 3 users of the events exist: - Lockdep - irqsoff and preemptoff tracers - irqs and preempt trace events The unification cleans up several ifdefs and makes the code in preempt tracer and irqsoff tracers simpler. It gets rid of all the horrific ifdeferry around PROVE_LOCKING and makes configuration of the different users of the tracepoints more easy and understandable. It also gets rid of the time_* function calls from the lockdep hooks used to call into the preemptirq tracer which is not needed anymore. The negative delta in lines of code in this patch is quite large too. In the patch we introduce a new CONFIG option PREEMPTIRQ_TRACEPOINTS as a single point for registering probes onto the tracepoints. With this, the web of config options for preempt/irq toggle tracepoints and its users becomes: PREEMPT_TRACER PREEMPTIRQ_EVENTS IRQSOFF_TRACER PROVE_LOCKING | | \ | | \ (selects) / \ \ (selects) / TRACE_PREEMPT_TOGGLE ----> TRACE_IRQFLAGS \ / \ (depends on) / PREEMPTIRQ_TRACEPOINTS Other than the performance tests mentioned in the previous patch, I also ran the locking API test suite. I verified that all tests cases are passing. I also injected issues by not registering lockdep probes onto the tracepoints and I see failures to confirm that the probes are indeed working. This series + lockdep probes not registered (just to inject errors): [ 0.000000] hard-irqs-on + irq-safe-A/21: ok | ok | ok | [ 0.000000] soft-irqs-on + irq-safe-A/21: ok | ok | ok | [ 0.000000] sirq-safe-A => hirqs-on/12:FAILED|FAILED| ok | [ 0.000000] sirq-safe-A => hirqs-on/21:FAILED|FAILED| ok | [ 0.000000] hard-safe-A + irqs-on/12:FAILED|FAILED| ok | [ 0.000000] soft-safe-A + irqs-on/12:FAILED|FAILED| ok | [ 0.000000] hard-safe-A + irqs-on/21:FAILED|FAILED| ok | [ 0.000000] soft-safe-A + irqs-on/21:FAILED|FAILED| ok | [ 0.000000] hard-safe-A + unsafe-B #1/123: ok | ok | ok | [ 0.000000] soft-safe-A + unsafe-B #1/123: ok | ok | ok | With this series + lockdep probes registered, all locking tests pass: [ 0.000000] hard-irqs-on + irq-safe-A/21: ok | ok | ok | [ 0.000000] soft-irqs-on + irq-safe-A/21: ok | ok | ok | [ 0.000000] sirq-safe-A => hirqs-on/12: ok | ok | ok | [ 0.000000] sirq-safe-A => hirqs-on/21: ok | ok | ok | [ 0.000000] hard-safe-A + irqs-on/12: ok | ok | ok | [ 0.000000] soft-safe-A + irqs-on/12: ok | ok | ok | [ 0.000000] hard-safe-A + irqs-on/21: ok | ok | ok | [ 0.000000] soft-safe-A + irqs-on/21: ok | ok | ok | [ 0.000000] hard-safe-A + unsafe-B #1/123: ok | ok | ok | [ 0.000000] soft-safe-A + unsafe-B #1/123: ok | ok | ok | Link: http://lkml.kernel.org/r/20180730222423.196630-4-joel@joelfernandes.org Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-21pid: Implement PIDTYPE_TGIDEric W. Biederman
Everywhere except in the pid array we distinguish between a tasks pid and a tasks tgid (thread group id). Even in the enumeration we want that distinction sometimes so we have added __PIDTYPE_TGID. With leader_pid we almost have an implementation of PIDTYPE_TGID in struct signal_struct. Add PIDTYPE_TGID as a first class member of the pid_type enumeration and into the pids array. Then remove the __PIDTYPE_TGID special case and the leader_pid in signal_struct. The net size increase is just an extra pointer added to struct pid and an extra pair of pointers of an hlist_node added to task_struct. The effect on code maintenance is the removal of a number of special cases today and the potential to remove many more special cases as PIDTYPE_TGID gets used to it's fullest. The long term potential is allowing zombie thread group leaders to exit, which will remove a lot more special cases in the code. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-07-21pids: Move the pgrp and session pid pointers from task_struct to signal_structEric W. Biederman
To access these fields the code always has to go to group leader so going to signal struct is no loss and is actually a fundamental simplification. This saves a little bit of memory by only allocating the pid pointer array once instead of once for every thread, and even better this removes a few potential races caused by the fact that group_leader can be changed by de_thread, while signal_struct can not. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-07-21pids: Initialize leader_pid in init_taskEric W. Biederman
This is cheap and no cost so we might as well. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-07-20x86/mm/pti: Introduce pti_finalize()Joerg Roedel
Introduce a new function to finalize the kernel mappings for the userspace page-table after all ro/nx protections have been applied to the kernel mappings. Also move the call to pti_clone_kernel_text() to that function so that it will run on 32 bit kernels too. Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Pavel Machek <pavel@ucw.cz> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: linux-mm@kvack.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Laight <David.Laight@aculab.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Eduardo Valentin <eduval@amazon.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Will Deacon <will.deacon@arm.com> Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Waiman Long <llong@redhat.com> Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca> Cc: joro@8bytes.org Link: https://lkml.kernel.org/r/1531906876-13451-30-git-send-email-joro@8bytes.org
2018-07-20sched/clock: Enable sched clock earlyPavel Tatashin
Allow sched_clock() to be used before schec_clock_init() is called. This provides a way to get early boot timestamps on machines with unstable clocks. Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: steven.sistare@oracle.com Cc: daniel.m.jordan@oracle.com Cc: linux@armlinux.org.uk Cc: schwidefsky@de.ibm.com Cc: heiko.carstens@de.ibm.com Cc: john.stultz@linaro.org Cc: sboyd@codeaurora.org Cc: hpa@zytor.com Cc: douly.fnst@cn.fujitsu.com Cc: peterz@infradead.org Cc: prarit@redhat.com Cc: feng.tang@intel.com Cc: pmladek@suse.com Cc: gnomes@lxorguk.ukuu.org.uk Cc: linux-s390@vger.kernel.org Cc: boris.ostrovsky@oracle.com Cc: jgross@suse.com Cc: pbonzini@redhat.com Link: https://lkml.kernel.org/r/20180719205545.16512-24-pasha.tatashin@oracle.com
2018-07-20sched/clock: Move sched clock initialization and merge with generic clockPavel Tatashin
sched_clock_postinit() initializes a generic clock on systems where no other clock is provided. This function may be called only after timekeeping_init(). Rename sched_clock_postinit to generic_clock_inti() and call it from sched_clock_init(). Move the call for sched_clock_init() until after time_init(). Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: steven.sistare@oracle.com Cc: daniel.m.jordan@oracle.com Cc: linux@armlinux.org.uk Cc: schwidefsky@de.ibm.com Cc: heiko.carstens@de.ibm.com Cc: john.stultz@linaro.org Cc: sboyd@codeaurora.org Cc: hpa@zytor.com Cc: douly.fnst@cn.fujitsu.com Cc: prarit@redhat.com Cc: feng.tang@intel.com Cc: pmladek@suse.com Cc: gnomes@lxorguk.ukuu.org.uk Cc: linux-s390@vger.kernel.org Cc: boris.ostrovsky@oracle.com Cc: jgross@suse.com Cc: pbonzini@redhat.com Link: https://lkml.kernel.org/r/20180719205545.16512-23-pasha.tatashin@oracle.com
2018-07-18kbuild: Add build salt to the kernel and modulesLaura Abbott
In Fedora, the debug information is packaged separately (foo-debuginfo) and can be installed separately. There's been a long standing issue where only one version of a debuginfo info package can be installed at a time. There's been an effort for Fedora for parallel debuginfo to rectify this problem. Part of the requirement to allow parallel debuginfo to work is that build ids are unique between builds. The existing upstream rpm implementation ensures this by re-calculating the build-id using the version and release as a seed. This doesn't work 100% for the kernel because of the vDSO which is its own binary and doesn't get updated when embedded. Fix this by adding some data in an ELF note for both the kernel and modules. The data is controlled via a Kconfig option so distributions can set it to an appropriate value to ensure uniqueness between builds. Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-06-30Merge tag 'kbuild-fixes-v4.18' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild fixes from Masahiro Yamada: - introduce __diag_* macros and suppress -Wattribute-alias warnings from GCC 8 - fix stack protector test script for x86_64 - fix line number handling in Kconfig - document that '#' starts a comment in Kconfig - handle P_SYMBOL property in dump debugging of Kconfig - correct help message of LD_DEAD_CODE_DATA_ELIMINATION - fix occasional segmentation faults in Kconfig * tag 'kbuild-fixes-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kconfig: loop boundary condition fix kbuild: reword help of LD_DEAD_CODE_DATA_ELIMINATION kconfig: handle P_SYMBOL in print_symbol() kconfig: document Kconfig source file comments kconfig: fix line numbers for if-entries in menu tree stack-protector: Fix test with 32-bit userland and CONFIG_64BIT=y powerpc: Remove -Wattribute-alias pragmas disable -Wattribute-alias warning for SYSCALL_DEFINEx() kbuild: add macro for controlling warnings to linux/compiler.h
2018-06-28kbuild: reword help of LD_DEAD_CODE_DATA_ELIMINATIONMasahiro Yamada
Since commit 5d20ee3192a5 ("kbuild: Allow LD_DEAD_CODE_DATA_ELIMINATION to be selectable if enabled"), HAVE_LD_DEAD_CODE_DATA_ELIMINATION is supposed to be selected by architectures that are capable of this functionality. LD_DEAD_CODE_DATA_ELIMINATION is now users' selection. Update the help message. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-06-25init/Kconfig: add an option for uncompressed kernelVasily Gorbik
Add "None" as the kernel compression mode. This option is useful for debugging the kernel in slow simulation environments, where decompressing and moving the kernel is awfully slow. Uncompressed kernel implementation might allow early boot code to skip the decompressor and jump right at uncompressed kernel image entry point. Platforms implementing that should define HAVE_KERNEL_UNCOMPRESSED. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-14dma-mapping: move all DMA mapping code to kernel/dmaChristoph Hellwig
Currently the code is split over various files with dma- prefixes in the lib/ and drives/base directories, and the number of files keeps growing. Move them into a single directory to keep the code together and remove the file name prefixes. To match the irq infrastructure this directory is placed under the kernel/ directory. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-06-13Merge tag 'kbuild-v4.18-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull more Kbuild updates from Masahiro Yamada: - fix some bugs introduced by the recent Kconfig syntax extension - add some symbols about compiler information in Kconfig, such as CC_IS_GCC, CC_IS_CLANG, GCC_VERSION, etc. - test compiler capability for the stack protector in Kconfig, and clean-up Makefile - test compiler capability for GCC-plugins in Kconfig, and clean-up Makefile - allow to enable GCC-plugins for COMPILE_TEST - test compiler capability for KCOV in Kconfig and correct dependency - remove auto-detect mode of the GCOV format, which is now more nicely handled in Kconfig - test compiler capability for mprofile-kernel on PowerPC, and clean-up Makefile - misc cleanups * tag 'kbuild-v4.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: linux/linkage.h: replace VMLINUX_SYMBOL_STR() with __stringify() kconfig: fix localmodconfig sh: remove no-op macro VMLINUX_SYMBOL() powerpc/kbuild: move -mprofile-kernel check to Kconfig Documentation: kconfig: add recommended way to describe compiler support gcc-plugins: disable GCC_PLUGIN_STRUCTLEAK_BYREF_ALL for COMPILE_TEST gcc-plugins: allow to enable GCC_PLUGINS for COMPILE_TEST gcc-plugins: test plugin support in Kconfig and clean up Makefile gcc-plugins: move GCC version check for PowerPC to Kconfig kcov: test compiler capability in Kconfig and correct dependency gcov: remove CONFIG_GCOV_FORMAT_AUTODETECT arm64: move GCC version check for ARCH_SUPPORTS_INT128 to Kconfig kconfig: add CC_IS_CLANG and CLANG_VERSION kconfig: add CC_IS_GCC and GCC_VERSION stack-protector: test compiler capability in Kconfig and drop AUTO mode kbuild: fix endless syncconfig in case arch Makefile sets CROSS_COMPILE
2018-06-10Merge branch 'core-rseq-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull restartable sequence support from Thomas Gleixner: "The restartable sequences syscall (finally): After a lot of back and forth discussion and massive delays caused by the speculative distraction of maintainers, the core set of restartable sequences has finally reached a consensus. It comes with the basic non disputed core implementation along with support for arm, powerpc and x86 and a full set of selftests It was exposed to linux-next earlier this week, so it does not fully comply with the merge window requirements, but there is really no point to drag it out for yet another cycle" * 'core-rseq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rseq/selftests: Provide Makefile, scripts, gitignore rseq/selftests: Provide parametrized tests rseq/selftests: Provide basic percpu ops test rseq/selftests: Provide basic test rseq/selftests: Provide rseq library selftests/lib.mk: Introduce OVERRIDE_TARGETS powerpc: Wire up restartable sequences system call powerpc: Add syscall detection for restartable sequences powerpc: Add support for restartable sequences x86: Wire up restartable sequence system call x86: Add support for restartable sequences arm: Wire up restartable sequences system call arm: Add syscall detection for restartable sequences arm: Add restartable sequences support rseq: Introduce restartable sequences system call uapi/headers: Provide types_32_64.h
2018-06-08kconfig: add CC_IS_CLANG and CLANG_VERSIONMasahiro Yamada
This will be useful to describe the clang version dependency. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Kees Cook <keescook@chromium.org>
2018-06-08kconfig: add CC_IS_GCC and GCC_VERSIONMasahiro Yamada
This will be useful to specify the required compiler version, like this: config FOO bool "Use Foo" depends on GCC_VERSION >= 40800 help This feature requires GCC 4.8 or newer. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Kees Cook <keescook@chromium.org>
2018-06-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: 1) Add Maglev hashing scheduler to IPVS, from Inju Song. 2) Lots of new TC subsystem tests from Roman Mashak. 3) Add TCP zero copy receive and fix delayed acks and autotuning with SO_RCVLOWAT, from Eric Dumazet. 4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard Brouer. 5) Add ttl inherit support to vxlan, from Hangbin Liu. 6) Properly separate ipv6 routes into their logically independant components. fib6_info for the routing table, and fib6_nh for sets of nexthops, which thus can be shared. From David Ahern. 7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP messages from XDP programs. From Nikita V. Shirokov. 8) Lots of long overdue cleanups to the r8169 driver, from Heiner Kallweit. 9) Add BTF ("BPF Type Format"), from Martin KaFai Lau. 10) Add traffic condition monitoring to iwlwifi, from Luca Coelho. 11) Plumb extack down into fib_rules, from Roopa Prabhu. 12) Add Flower classifier offload support to igb, from Vinicius Costa Gomes. 13) Add UDP GSO support, from Willem de Bruijn. 14) Add documentation for eBPF helpers, from Quentin Monnet. 15) Add TLS tx offload to mlx5, from Ilya Lesokhin. 16) Allow applications to be given the number of bytes available to read on a socket via a control message returned from recvmsg(), from Soheil Hassas Yeganeh. 17) Add x86_32 eBPF JIT compiler, from Wang YanQing. 18) Add AF_XDP sockets, with zerocopy support infrastructure as well. From Björn Töpel. 19) Remove indirect load support from all of the BPF JITs and handle these operations in the verifier by translating them into native BPF instead. From Daniel Borkmann. 20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha. 21) Allow XDP programs to do lookups in the main kernel routing tables for forwarding. From David Ahern. 22) Allow drivers to store hardware state into an ELF section of kernel dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy. 23) Various RACK and loss detection improvements in TCP, from Yuchung Cheng. 24) Add TCP SACK compression, from Eric Dumazet. 25) Add User Mode Helper support and basic bpfilter infrastructure, from Alexei Starovoitov. 26) Support ports and protocol values in RTM_GETROUTE, from Roopa Prabhu. 27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard Brouer. 28) Add lots of forwarding selftests, from Petr Machata. 29) Add generic network device failover driver, from Sridhar Samudrala. * ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits) strparser: Add __strp_unpause and use it in ktls. rxrpc: Fix terminal retransmission connection ID to include the channel net: hns3: Optimize PF CMDQ interrupt switching process net: hns3: Fix for VF mailbox receiving unknown message net: hns3: Fix for VF mailbox cannot receiving PF response bnx2x: use the right constant Revert "net: sched: cls: Fix offloading when ingress dev is vxlan" net: dsa: b53: Fix for brcm tag issue in Cygnus SoC enic: fix UDP rss bits netdev-FAQ: clarify DaveM's position for stable backports rtnetlink: validate attributes in do_setlink() mlxsw: Add extack messages for port_{un, }split failures netdevsim: Add extack error message for devlink reload devlink: Add extack to reload and port_{un, }split operations net: metrics: add proper netlink validation ipmr: fix error path when ipmr_new_table fails ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds net: hns3: remove unused hclgevf_cfg_func_mta_filter netfilter: provide udp*_lib_lookup for nf_tproxy qed*: Utilize FW 8.37.2.0 ...
2018-06-06Merge tag 'audit-pr-20180605' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit Pull audit updates from Paul Moore: "Another reasonable chunk of audit changes for v4.18, thirteen patches in total. The thirteen patches can mostly be broken down into one of four categories: general bug fixes, accessor functions for audit state stored in the task_struct, negative filter matches on executable names, and extending the (relatively) new seccomp logging knobs to the audit subsystem. The main driver for the accessor functions from Richard are the changes we're working on to associate audit events with containers, but I think they have some standalone value too so I figured it would be good to get them in now. The seccomp/audit patches from Tyler apply the seccomp logging improvements from a few releases ago to audit's seccomp logging; starting with this patchset the changes in /proc/sys/kernel/seccomp/actions_logged should apply to both the standard kernel logging and audit. As usual, everything passes the audit-testsuite and it happens to merge cleanly with your tree" [ Heh, except it had trivial merge conflicts with the SELinux tree that also came in from Paul - Linus ] * tag 'audit-pr-20180605' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: audit: Fix wrong task in comparison of session ID audit: use existing session info function audit: normalize loginuid read access audit: use new audit_context access funciton for seccomp_actions_logged audit: use inline function to set audit context audit: use inline function to get audit context audit: convert sessionid unset to a macro seccomp: Don't special case audited processes when logging seccomp: Audit attempts to modify the actions_logged sysctl seccomp: Configurable separator for the actions_logged string seccomp: Separate read and write code for actions_logged sysctl audit: allow not equal op for audit by executable audit: add syscall information to FEATURE_CHANGE records
2018-06-06Merge tag 'kconfig-v4.18' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kconfig updates from Masahiro Yamada: "Kconfig now supports new functionality to perform textual substitution. It has been a while since Linus suggested to move compiler option tests from makefiles to Kconfig. Finally, here it is. The implementation has been generalized into a Make-like macro language. Some built-in functions such as 'shell' are provided. Variables and user-defined functions are also supported so that 'cc-option', 'ld-option', etc. are implemented as macros. Summary: - refactor package checks for building {m,n,q,g}conf - remove unused/unmaintained localization support - remove Kbuild cache - drop CONFIG_CROSS_COMPILE support - replace 'option env=' with direct variable expansion - add built-in functions such as 'shell' - support variables and user-defined functions - add helper macros as as 'cc-option' - add unit tests and a document of the new macro language - add 'testconfig' to help - fix warnings from GCC 8.1" * tag 'kconfig-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (30 commits) kconfig: Avoid format overflow warning from GCC 8.1 kbuild: Move last word of nconfig help to the previous line kconfig: Add testconfig into make help output kconfig: add basic helper macros to scripts/Kconfig.include kconfig: show compiler version text in the top comment kconfig: test: add Kconfig macro language tests Documentation: kconfig: document a new Kconfig macro language kconfig: error out if a recursive variable references itself kconfig: add 'filename' and 'lineno' built-in variables kconfig: add 'info', 'warning-if', and 'error-if' built-in functions kconfig: expand lefthand side of assignment statement kconfig: support append assignment operator kconfig: support simply expanded variable kconfig: support user-defined function and recursively expanded variable kconfig: begin PARAM state only when seeing a command keyword kconfig: replace $(UNAME_RELEASE) with function call kconfig: add 'shell' built-in function kconfig: add built-in function support kconfig: make default prompt of mainmenu less specific kconfig: remove sym_expand_string_value() ...
2018-06-06Merge tag 'kbuild-v4.18' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - improve fixdep to coalesce consecutive slashes in dep-files - fix some issues of the maintainer string generation in deb-pkg script - remove unused CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX and clean-up several tools and linker scripts - clean-up modpost - allow to enable the dead code/data elimination for PowerPC in EXPERT mode - improve two coccinelle scripts for better performance - pass endianness and machine size flags to sparse for all architecture - misc fixes * tag 'kbuild-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits) kbuild: add machine size to CHECKFLAGS kbuild: add endianness flag to CHEKCFLAGS kbuild: $(CHECK) doesnt need NOSTDINC_FLAGS twice scripts: Fixed printf format mismatch scripts/tags.sh: use `find` for $ALLSOURCE_ARCHS generation coccinelle: deref_null: improve performance coccinelle: mini_lock: improve performance powerpc: Allow LD_DEAD_CODE_DATA_ELIMINATION to be selected kbuild: Allow LD_DEAD_CODE_DATA_ELIMINATION to be selectable if enabled kbuild: LD_DEAD_CODE_DATA_ELIMINATION no -ffunction-sections/-fdata-sections for module build kbuild: Fix asm-generic/vmlinux.lds.h for LD_DEAD_CODE_DATA_ELIMINATION modpost: constify *modname function argument where possible modpost: remove redundant is_vmlinux() test modpost: use strstarts() helper more widely modpost: pass struct elf_info pointer to get_modinfo() checkpatch: remove VMLINUX_SYMBOL() check vmlinux.lds.h: remove no-op macro VMLINUX_SYMBOL() kbuild: remove CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX export.h: remove code for prefixing symbols with underscore depmod.sh: remove symbol prefix support ...
2018-06-06rseq: Introduce restartable sequences system callMathieu Desnoyers
Expose a new system call allowing each thread to register one userspace memory area to be used as an ABI between kernel and user-space for two purposes: user-space restartable sequences and quick access to read the current CPU number value from user-space. * Restartable sequences (per-cpu atomics) Restartables sequences allow user-space to perform update operations on per-cpu data without requiring heavy-weight atomic operations. The restartable critical sections (percpu atomics) work has been started by Paul Turner and Andrew Hunter. It lets the kernel handle restart of critical sections. [1] [2] The re-implementation proposed here brings a few simplifications to the ABI which facilitates porting to other architectures and speeds up the user-space fast path. Here are benchmarks of various rseq use-cases. Test hardware: arm32: ARMv7 Processor rev 4 (v7l) "Cubietruck", 2-core x86-64: Intel E5-2630 v3@2.40GHz, 16-core, hyperthreading The following benchmarks were all performed on a single thread. * Per-CPU statistic counter increment getcpu+atomic (ns/op) rseq (ns/op) speedup arm32: 344.0 31.4 11.0 x86-64: 15.3 2.0 7.7 * LTTng-UST: write event 32-bit header, 32-bit payload into tracer per-cpu buffer getcpu+atomic (ns/op) rseq (ns/op) speedup arm32: 2502.0 2250.0 1.1 x86-64: 117.4 98.0 1.2 * liburcu percpu: lock-unlock pair, dereference, read/compare word getcpu+atomic (ns/op) rseq (ns/op) speedup arm32: 751.0 128.5 5.8 x86-64: 53.4 28.6 1.9 * jemalloc memory allocator adapted to use rseq Using rseq with per-cpu memory pools in jemalloc at Facebook (based on rseq 2016 implementation): The production workload response-time has 1-2% gain avg. latency, and the P99 overall latency drops by 2-3%. * Reading the current CPU number Speeding up reading the current CPU number on which the caller thread is running is done by keeping the current CPU number up do date within the cpu_id field of the memory area registered by the thread. This is done by making scheduler preemption set the TIF_NOTIFY_RESUME flag on the current thread. Upon return to user-space, a notify-resume handler updates the current CPU value within the registered user-space memory area. User-space can then read the current CPU number directly from memory. Keeping the current cpu id in a memory area shared between kernel and user-space is an improvement over current mechanisms available to read the current CPU number, which has the following benefits over alternative approaches: - 35x speedup on ARM vs system call through glibc - 20x speedup on x86 compared to calling glibc, which calls vdso executing a "lsl" instruction, - 14x speedup on x86 compared to inlined "lsl" instruction, - Unlike vdso approaches, this cpu_id value can be read from an inline assembly, which makes it a useful building block for restartable sequences. - The approach of reading the cpu id through memory mapping shared between kernel and user-space is portable (e.g. ARM), which is not the case for the lsl-based x86 vdso. On x86, yet another possible approach would be to use the gs segment selector to point to user-space per-cpu data. This approach performs similarly to the cpu id cache, but it has two disadvantages: it is not portable, and it is incompatible with existing applications already using the gs segment selector for other purposes. Benchmarking various approaches for reading the current CPU number: ARMv7 Processor rev 4 (v7l) Machine model: Cubietruck - Baseline (empty loop): 8.4 ns - Read CPU from rseq cpu_id: 16.7 ns - Read CPU from rseq cpu_id (lazy register): 19.8 ns - glibc 2.19-0ubuntu6.6 getcpu: 301.8 ns - getcpu system call: 234.9 ns x86-64 Intel(R) Xeon(R) CPU E5-2630 v3 @ 2.40GHz: - Baseline (empty loop): 0.8 ns - Read CPU from rseq cpu_id: 0.8 ns - Read CPU from rseq cpu_id (lazy register): 0.8 ns - Read using gs segment selector: 0.8 ns - "lsl" inline assembly: 13.0 ns - glibc 2.19-0ubuntu6 getcpu: 16.6 ns - getcpu system call: 53.9 ns - Speed (benchmark taken on v8 of patchset) Running 10 runs of hackbench -l 100000 seems to indicate, contrary to expectations, that enabling CONFIG_RSEQ slightly accelerates the scheduler: Configuration: 2 sockets * 8-core Intel(R) Xeon(R) CPU E5-2630 v3 @ 2.40GHz (directly on hardware, hyperthreading disabled in BIOS, energy saving disabled in BIOS, turboboost disabled in BIOS, cpuidle.off=1 kernel parameter), with a Linux v4.6 defconfig+localyesconfig, restartable sequences series applied. * CONFIG_RSEQ=n avg.: 41.37 s std.dev.: 0.36 s * CONFIG_RSEQ=y avg.: 40.46 s std.dev.: 0.33 s - Size On x86-64, between CONFIG_RSEQ=n/y, the text size increase of vmlinux is 567 bytes, and the data size increase of vmlinux is 5696 bytes. [1] https://lwn.net/Articles/650333/ [2] http://www.linuxplumbersconf.org/2013/ocw/system/presentations/1695/original/LPC%20-%20PerCpu%20Atomics.pdf Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Joel Fernandes <joelaf@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Watson <davejwatson@fb.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Chris Lameter <cl@linux.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Andrew Hunter <ahh@google.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com> Cc: Paul Turner <pjt@google.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ben Maurer <bmaurer@fb.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: linux-api@vger.kernel.org Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20151027235635.16059.11630.stgit@pjt-glaptop.roam.corp.google.com Link: http://lkml.kernel.org/r/20150624222609.6116.86035.stgit@kitami.mtv.corp.google.com Link: https://lkml.kernel.org/r/20180602124408.8430-3-mathieu.desnoyers@efficios.com